Researchers uncovered skull fragments of Machairoceratops cronusi in 77-million-year-old mudstone from the Wahweap Formation in southern Utah. Unlike other horned dinosaurs, the roughly 8-meter-long M. cronusi had two grooved horns with spatula-like tips bowed forward from the back of its neck shield. The grooves’ function baffles researchers.

A different research team found a younger cousin of M. cronusi in Montana’s Judith River Formation. Spiclypeus shipporum lived about 76 million years ago and had distinct brow horns that protruded sideways from its skull along with unusual spikes on its neck shield — some pointing outward, others bent forward.

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